The present embodiments relate to magnetic resonance imaging (MRI). In particular, sensitivity encoding (SENSE) reconstruction in MRI for a reduced field of view is provided.
In applications such as cardiac imaging, it is sometimes beneficial to select a smaller field-of-view (FOV) as compared to the size of the whole object (e.g., patient). This reduced FOV may allow an increase in image resolution and/or save data acquisition time.
Reduced FOV (rFOV) with SENSE reconstruction causes extra folding in the image domain around the edges of the image. This folding is in addition to the folding due to subsampling for parallel imaging. SENSE-like methods may not resolve the aliasing appropriately under reduced FOV unless denser sampling grids are used for coil sensitivity estimation.
Coil-by-coil reconstruction methods, such as GRAPPA, are robust to FOV limitations because the interpolation kernels may have more localized shapes than the coil sensitivities. These localized shapes may be well-represented in sparse sampling grids. However, GRAPPA reconstructions exhibit noise in high acceleration rates. Noise may be mitigated in SENSE via regularization.